Heart failure is an insufficient pumping of the blood to meet the body's needs. By 2030, about 18 million adults will be living with heart failure. Cardiomyopathy, or heart muscle disease, often leads to heart failure. To develop more effective, specific, targeted therapeutics, it is important to understand the molecular mechanisms that underlie cardiomyopathies. Calcineurin-CRTC- CREB signaling axis is a novel pathway that has not yet been studied in the heart. I will use the genetically tractable Drosophila model to elucidate the role of calcineurin-activated CRTC/CREB pathway in the heart. Results from this study will provide a potentially new mechanism to target drug development. While calcineurin is critical in the induction of hypertrophic and dilated cardiomyopathy, a mechanism of action involving CRTC/CREB has yet to be determined. I hypothesize that CRTC/CREB activation by calcineurin is an alternative pathway to canonical NFAT activation in the heart that contributes to maintenance of adult cardiac structure and function. I propose to test this hypothesis by studying the calcineurin-CRTC axis in the Drosophila heart model. I will determine heart-autonomous and non-autonomous roles of this pathway in establishing and maintaining cardiac homeostasis. Additionally, the effects of CRTC regulators and co-activators on the heart structure and function will be studied. Finally, potential effectors of CRTC signaling will be identified through RNAseq analysis and prioritized for further functional characterization.